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INFO: task hung in switchdev_deferred_process_work (2)

Status: upstream: reported on 2025/09/22 08:30
Reported-by: syzbot+65c189d5c26b67e252f2@syzkaller.appspotmail.com
First crash: 5d11h, last: 5d11h
▶ ▼ Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in switchdev_deferred_process_work (2) net 1 C inconclusive 1226 445d 1888d 26/29 fixed on 2024/07/09 19:14
linux-6.6 INFO: task hung in switchdev_deferred_process_work 1 1 66d 66d 0/2 upstream: reported on 2025/07/23 04:22
upstream INFO: task hung in switchdev_deferred_process_work net 1 35 2178d 2714d 0/29 closed as invalid on 2019/10/23 07:26
upstream INFO: task hung in switchdev_deferred_process_work (3) net 1 C inconclusive 536 8h45m 414d 0/29 upstream: reported C repro on 2024/08/08 21:14
linux-5.15 INFO: task hung in switchdev_deferred_process_work 1 1 899d 899d 0/3 auto-obsoleted due to no activity on 2023/08/10 05:46
linux-4.19 INFO: task hung in switchdev_deferred_process_work 1 95 951d 2029d 0/1 upstream: reported on 2020/03/08 04:06
linux-4.14 INFO: task hung in switchdev_deferred_process_work 1 1 1240d 1240d 0/1 auto-obsoleted due to no activity on 2022/09/03 16:45
linux-5.15 INFO: task hung in switchdev_deferred_process_work (2) 1 36 553d 625d 0/3 auto-obsoleted due to no activity on 2024/06/01 16:21
linux-5.15 INFO: task hung in switchdev_deferred_process_work (3) 1 8 337d 480d 0/3 auto-obsoleted due to no activity on 2025/02/02 03:46
linux-6.1 INFO: task hung in switchdev_deferred_process_work 1 8 444d 607d 0/3 auto-obsoleted due to no activity on 2024/10/18 09:59

Sample crash report:
INFO: task kworker/1:19:6725 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:19    state:D stack:24096 pid:6725  ppid:2      flags:0x00004000
Workqueue: events switchdev_deferred_process_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747
 switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task kworker/u4:25:8021 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:25   state:D stack:20448 pid:8021  ppid:2      flags:0x00004000
Workqueue: phy17 ieee80211_iface_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 exp_funnel_lock kernel/rcu/tree_exp.h:314 [inline]
 synchronize_rcu_expedited+0x71b/0x830 kernel/rcu/tree_exp.h:962
 __sta_info_destroy+0x33/0x50 net/mac80211/sta_info.c:1345
 ieee80211_ibss_sta_expire net/mac80211/ibss.c:1278 [inline]
 ieee80211_sta_merge_ibss net/mac80211/ibss.c:1299 [inline]
 ieee80211_ibss_work+0x77c/0x10b0 net/mac80211/ibss.c:1708
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task syz-executor:8993 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21504 pid:8993  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 exp_funnel_lock kernel/rcu/tree_exp.h:314 [inline]
 synchronize_rcu_expedited+0x71b/0x830 kernel/rcu/tree_exp.h:962
 namespace_unlock+0x1e3/0x3c0 fs/namespace.c:1493
 do_umount fs/namespace.c:1717 [inline]
 path_umount+0xeff/0xf80 fs/namespace.c:1800
 ksys_umount fs/namespace.c:1823 [inline]
 __do_sys_umount fs/namespace.c:1828 [inline]
 __se_sys_umount fs/namespace.c:1826 [inline]
 __x64_sys_umount+0x125/0x160 fs/namespace.c:1826
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9dca18ff57
RSP: 002b:00007ffe39df7208 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f9dca211c2d RCX: 00007f9dca18ff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe39df72c0
RBP: 00007ffe39df72c0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe39df8350
R13: 00007f9dca211c2d R14: 00000000000a6ec5 R15: 00007ffe39df8390
 </TASK>
INFO: task syz-executor:9059 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21600 pid:9059  ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747
 exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962
 namespace_unlock+0x1e3/0x3c0 fs/namespace.c:1493
 do_umount fs/namespace.c:1717 [inline]
 path_umount+0xeff/0xf80 fs/namespace.c:1800
 ksys_umount fs/namespace.c:1823 [inline]
 __do_sys_umount fs/namespace.c:1828 [inline]
 __se_sys_umount fs/namespace.c:1826 [inline]
 __x64_sys_umount+0x125/0x160 fs/namespace.c:1826
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f120f98ff57
RSP: 002b:00007ffd3ffaa598 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f120fa11c2d RCX: 00007f120f98ff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd3ffaa650
RBP: 00007ffd3ffaa650 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd3ffab6e0
R13: 00007f120fa11c2d R14: 00000000000a6667 R15: 00007ffd3ffab720
 </TASK>
INFO: task syz.7.1512:10753 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.1512      state:D stack:24832 pid:10753 ppid:7602   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 synchronize_rcu_expedited+0x67d/0x830 kernel/rcu/tree_exp.h:977
 synchronize_rcu+0x11c/0x380 kernel/rcu/tree.c:3580
 __nf_tables_abort net/netfilter/nf_tables_api.c:10177 [inline]
 nf_tables_abort+0x5435/0x6430 net/netfilter/nf_tables_api.c:10196
 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:585 [inline]
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:639 [inline]
 nfnetlink_rcv+0x1b03/0x2170 net/netfilter/nfnetlink.c:657
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmsg net/socket.c:2602 [inline]
 __do_sys_sendmsg net/socket.c:2611 [inline]
 __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd2f878ec29
RSP: 002b:00007fd2f95ab038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd2f89d6090 RCX: 00007fd2f878ec29
RDX: 0000000000000040 RSI: 0000200000009b40 RDI: 0000000000000005
RBP: 00007fd2f8811e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd2f89d6128 R14: 00007fd2f89d6090 R15: 00007ffd02d42a88
 </TASK>
INFO: task dhcpcd:10761 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:24960 pid:10761 ppid:3932   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 exp_funnel_lock kernel/rcu/tree_exp.h:314 [inline]
 synchronize_rcu_expedited+0x71b/0x830 kernel/rcu/tree_exp.h:962
 synchronize_rcu+0x11c/0x380 kernel/rcu/tree.c:3580
 __unregister_prot_hook+0x3f7/0x570 net/packet/af_packet.c:383
 packet_do_bind+0x519/0xce0 net/packet/af_packet.c:3284
 __sys_bind+0x2f4/0x3f0 net/socket.c:1811
 __do_sys_bind net/socket.c:1822 [inline]
 __se_sys_bind net/socket.c:1820 [inline]
 __x64_sys_bind+0x76/0x80 net/socket.c:1820
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f72657a42d7
RSP: 002b:00007ffe7637a808 EFLAGS: 00000213 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 000055a049fb0580 RCX: 00007f72657a42d7
RDX: 0000000000000014 RSI: 00007ffe7637a820 RDI: 0000000000000003
RBP: 000055a0420ce4b0 R08: 00007f7265873ac0 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000213 R12: 0000000000000000
R13: 000055a049fafa60 R14: 0000000000000000 R15: 000055a0420e3ac0
 </TASK>
INFO: task dhcpcd:10768 blocked for more than 147 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:24960 pid:10768 ppid:3932   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 exp_funnel_lock kernel/rcu/tree_exp.h:314 [inline]
 synchronize_rcu_expedited+0x71b/0x830 kernel/rcu/tree_exp.h:962
 synchronize_rcu+0x11c/0x380 kernel/rcu/tree.c:3580
 __unregister_prot_hook+0x3f7/0x570 net/packet/af_packet.c:383
 packet_do_bind+0x519/0xce0 net/packet/af_packet.c:3284
 __sys_bind+0x2f4/0x3f0 net/socket.c:1811
 __do_sys_bind net/socket.c:1822 [inline]
 __se_sys_bind net/socket.c:1820 [inline]
 __x64_sys_bind+0x76/0x80 net/socket.c:1820
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f72657a42d7
RSP: 002b:00007ffe7637a808 EFLAGS: 00000213 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 000055a049fb0580 RCX: 00007f72657a42d7
RDX: 0000000000000014 RSI: 00007ffe7637a820 RDI: 0000000000000003
RBP: 000055a0420ce4b0 R08: 00007f7265873ac0 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000213 R12: 0000000000000000
R13: 000055a049fb0cf0 R14: 0000000000000000 R15: 000055a0420e3ac0
 </TASK>
INFO: task syz.8.1521:10775 blocked for more than 147 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1521      state:D stack:23776 pid:10775 ppid:8079   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 exp_funnel_lock kernel/rcu/tree_exp.h:314 [inline]
 synchronize_rcu_expedited+0x71b/0x830 kernel/rcu/tree_exp.h:962
 namespace_unlock+0x1e3/0x3c0 fs/namespace.c:1493
 drop_collected_mounts fs/namespace.c:1982 [inline]
 put_mnt_ns+0xdb/0x120 fs/namespace.c:4479
 free_nsproxy+0x49/0x3c0 kernel/nsproxy.c:191
 do_exit+0x939/0x2400 kernel/exit.c:879
 do_group_exit+0x217/0x2d0 kernel/exit.c:1022
 get_signal+0x1272/0x1350 kernel/signal.c:2871
 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f73c9b8ec29
RSP: 002b:00007f73caa550e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f73c9dd5fa8 RCX: 00007f73c9b8ec29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f73c9dd5fa8
RBP: 00007f73c9dd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f73c9dd6038 R14: 00007ffedd0c6a70 R15: 00007ffedd0c6b58
 </TASK>
INFO: task dhcpcd:10774 blocked for more than 148 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:24960 pid:10774 ppid:3932   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 exp_funnel_lock kernel/rcu/tree_exp.h:314 [inline]
 synchronize_rcu_expedited+0x71b/0x830 kernel/rcu/tree_exp.h:962
 synchronize_rcu+0x11c/0x380 kernel/rcu/tree.c:3580
 __unregister_prot_hook+0x3f7/0x570 net/packet/af_packet.c:383
 packet_do_bind+0x519/0xce0 net/packet/af_packet.c:3284
 __sys_bind+0x2f4/0x3f0 net/socket.c:1811
 __do_sys_bind net/socket.c:1822 [inline]
 __se_sys_bind net/socket.c:1820 [inline]
 __x64_sys_bind+0x76/0x80 net/socket.c:1820
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f72657a42d7
RSP: 002b:00007ffe7637a808 EFLAGS: 00000213 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 000055a049fb0580 RCX: 00007f72657a42d7
RDX: 0000000000000014 RSI: 00007ffe7637a820 RDI: 0000000000000003
RBP: 000055a0420ce4b0 R08: 00007f7265873ac0 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000213 R12: 0000000000000000
R13: 000055a049fb0680 R14: 0000000000000000 R15: 000055a0420e3ac0
 </TASK>
INFO: task dhcpcd:10776 blocked for more than 149 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:24960 pid:10776 ppid:3932   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 exp_funnel_lock kernel/rcu/tree_exp.h:314 [inline]
 synchronize_rcu_expedited+0x71b/0x830 kernel/rcu/tree_exp.h:962
 synchronize_rcu+0x11c/0x380 kernel/rcu/tree.c:3580
 __unregister_prot_hook+0x3f7/0x570 net/packet/af_packet.c:383
 packet_do_bind+0x519/0xce0 net/packet/af_packet.c:3284
 __sys_bind+0x2f4/0x3f0 net/socket.c:1811
 __do_sys_bind net/socket.c:1822 [inline]
 __se_sys_bind net/socket.c:1820 [inline]
 __x64_sys_bind+0x76/0x80 net/socket.c:1820
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f72657a42d7
RSP: 002b:00007ffe7637a808 EFLAGS: 00000213 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 000055a049fb0580 RCX: 00007f72657a42d7
RDX: 0000000000000014 RSI: 00007ffe7637a820 RDI: 0000000000000003
RBP: 000055a0420ce4b0 R08: 00007f7265873ac0 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000213 R12: 0000000000000000
R13: 000055a049fb0b20 R14: 0000000000000000 R15: 000055a0420e3ac0
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2b570 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2bd90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2abe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
1 lock held by klogd/3626:
2 locks held by getty/4029:
 #0: ffff88802f697098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
5 locks held by kworker/0:9/4845:
3 locks held by kworker/1:19/6725:
 #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #1: ffffc9000e1afd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104
4 locks held by kworker/u4:25/8021:
 #0: ffff888077c1e938 ((wq_completion)phy17){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004e5fd00 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #2: ffff888074114d40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1113 [inline]
 #2: ffff888074114d40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0xa0/0x10b0 net/mac80211/ibss.c:1680
 #3: ffff888077d11780 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_sta_expire net/mac80211/ibss.c:1256 [inline]
 #3: ffff888077d11780 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_sta_merge_ibss net/mac80211/ibss.c:1299 [inline]
 #3: ffff888077d11780 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x577/0x10b0 net/mac80211/ibss.c:1708
1 lock held by syz-executor/9059:
 #0: ffffffff8cb308b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #0: ffffffff8cb308b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962
3 locks held by kworker/1:3/10054:
 #0: ffff88814d5eb538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004e2fd00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4672
2 locks held by syz.7.1512/10753:
 #0: ffff88807e6a54b8 (&nft_net->commit_mutex){+.+.}-{3:3}, at: nf_tables_valid_genid+0x37/0x100 net/netfilter/nf_tables_api.c:10219
 #1: ffffffff8cb308b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
 #1: ffffffff8cb308b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
1 lock held by dhcpcd/10761:
 #0: ffff88805f918130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
 #0: ffff88805f918130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
1 lock held by dhcpcd/10768:
 #0: ffff888062274130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
 #0: ffff888062274130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
1 lock held by dhcpcd/10774:
 #0: ffff8880588cc130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
 #0: ffff8880588cc130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
1 lock held by dhcpcd/10776:
 #0: ffff88807c9ca130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
 #0: ffff88807c9ca130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
1 lock held by dhcpcd/10780:
 #0: ffff888057bde130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
 #0: ffff888057bde130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
1 lock held by syz.2.1524/10785:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492
1 lock held by syz-executor/10788:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10791:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10794:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10797:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10800:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by dhcpcd/10802:
 #0: ffff88808c51c130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1792 [inline]
 #0: ffff88808c51c130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3248
1 lock held by syz-executor/10804:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10807:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10811:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10813:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10816:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10820:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10825:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10827:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10829:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150
1 lock held by syz-executor/10833:
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd422e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x740/0xed0 net/core/rtnetlink.c:6150

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xeee/0xf30 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4845 Comm: kworker/0:9 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x77/0x290 mm/kasan/generic.c:189
Code: 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db <41> 80 39 00 0f 85 c1 01 00 00 49 ff c1 48 ff c3 75 ee e9 1c 01 00
RSP: 0018:ffffc9000d57e5b0 EFLAGS: 00000282
RAX: 0000000000000001 RBX: fffffffffffffffe RCX: ffffffff81386ffa
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc9000d57e718
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff52001aafce3
R10: fffff52001aafce5 R11: 1ffff92001aafce3 R12: 1ffff92001aafcda
R13: dffffc0000000000 R14: 0000000000000002 R15: dffffc0000000001
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ab2fe52730 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 memset+0x1e/0x40 mm/kasan/shadow.c:44
 unwind_next_frame+0xb8a/0x20b0 arch/x86/kernel/unwind_orc.c:546
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 kmem_cache_alloc_node+0x14d/0x320 mm/slub.c:3404
 __alloc_skb+0xfc/0x7e0 net/core/skbuff.c:505
 __netdev_alloc_skb+0x107/0x4d0 net/core/skbuff.c:579
 netdev_alloc_skb include/linux/skbuff.h:3229 [inline]
 dev_alloc_skb include/linux/skbuff.h:3242 [inline]
 ath6kl_usb_post_recv_transfers+0x207/0x6f0 drivers/net/wireless/ath/ath6kl/usb.c:428
 ath6kl_usb_start_recv_pipes drivers/net/wireless/ath/ath6kl/usb.c:498 [inline]
 hif_start drivers/net/wireless/ath/ath6kl/usb.c:703 [inline]
 ath6kl_usb_power_on+0x66/0x280 drivers/net/wireless/ath/ath6kl/usb.c:1062
 ath6kl_hif_power_on drivers/net/wireless/ath/ath6kl/hif-ops.h:136 [inline]
 ath6kl_core_init+0x1ce/0x10c0 drivers/net/wireless/ath/ath6kl/core.c:97
 ath6kl_usb_probe+0x144a/0x1540 drivers/net/wireless/ath/ath6kl/usb.c:1168
 usb_probe_interface+0x5a0/0xaf0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
 __device_attach+0x29b/0x460 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x175/0x200 drivers/base/bus.c:429
 __device_attach+0x29b/0x460 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_new_device+0xd4d/0x1620 drivers/usb/core/hub.c:2659
 hub_port_connect drivers/usb/core/hub.c:5517 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5657 [inline]
 port_event drivers/usb/core/hub.c:5817 [inline]
 hub_event+0x2d5e/0x54e0 drivers/usb/core/hub.c:5899
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/22 08:29 linux-6.1.y 363a599da6d9 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in switchdev_deferred_process_work
* Struck through repros no longer work on HEAD.